The Processing And Realization Of Positioning System Based On DTMB In Baseband

The system of digital television terrestria l broadcasting have already built in ma nycountry as the one fundamenta l establishment of metropolis.The sent signa l from la unchers ispowerful in power, low in frequency and wide in bandwidth, not only covers absolutely entirecity including ma ny build ing dense areas , and transmits not liable to be interferenced, butalso DTMB signa l structure is passable to measure pseudo-range.In short, positioning basedon digital television signa l has profound and lasting significa nce.This thesis researches crucia l techniques of positioning system based on digitaltelevision terrestria l broadcasting. The receiver design in baseband is fulfilled by analyzingthe operation principle of receiver. Positioning receiver based on FPGA and DSP is finished.The research of receiver techniques in baseband includes the digital filtering, signa l tracking,carrier tracking and code tracking. This thesis accomplishes the Modules of dela y andcorrela tion, early-code correla tion, FIR filter and raise cosine filter.Through field measurement of combined positioning system, the results show thatpositioning system based on digital television terrestria l broadcasting and the receiver designin baseband are feasible and correct. At the same time, it provides that combined positioningsystem with GNSS and digital television terrestria l broadcasting signa l is realizable incomplex circumsta nce of city.